Propeller



March 4, 1941.

E. HAWKINS PROPELLER Filed May 31, 1939 3 SheetsSheet 1 Inventor LBERTHAWKINS,

A iiorneys March 4, 1941. E, NS 2,234,120

PROPELLER Filed May 31, 1939 5 Sheets-Sheet 2 .A iiorneys UNITED STATESPATENT PROPELLER Elbert Hawkins Joliet, Ill. Application May 31, 1939,Serial No. 276,722

1 Claim.

The present invention relates to new and useful improvements inpropellers particularly for aeroplanes, although it will be understood,of course, that the invention may be used for any other purpose forwhich it may be found adapted I and desirable, such as on boats.

The primary object of the invention -is to provide, in a manner ashereinafter set forth, a propeller of the character described comprisinga novel construction, combination and arrangement of oppositely rotatingblades whereby the efficiency and life of the engine will be materiallyincreased.

Other objects of the invention are to provide a propeller of theaforementioned character which will be comparatively simple inconstruction, strong, durable, compact, light in weight and which may bemanufactured at lowcost.

All of the foregoing and still further objects and advantages of theinvention will become apparent from a study of the followingspecification, taken in connection with the accompanying drawingswherein like characters of reference designate corresponding partsthroughout the several views, and wherein:

Figure 1 is a view in side elevation of a propeller constructed inaccordance with the present invention.

Figure 2 is a viewin front elevation thereof.

Figure 3 is a view in vertical longitudinal section through theinvention.

Figure 4 is a cross sectional view, taken substantially on the line 4-4of Fig. 3.

Figure 5 is a view in front elevation of one of the blades andits hub.

. Figure 6 is a plan view of one of the hubs.

Figure 7 is a vertical sectional view through one of the hubs, takensubstantially on theline II of Fig. 6.

Referring now to the drawings in detail, it will' be seen that theembodiment of the invention which has been illustrated comprises acasing of suitable metal which is designated generally by the referencenumeral I. -The casing I is F stationary and includes a pair ofcomplemental sections 2 and 3 which are bolted together, as at 4. Thecasing I further includes an extension 5 on its rear end which isbolted, as at 6, to the forward end of an engine I. The forward end ofthe casing I is closed by .a housing 8 of the construction shown toadvantage in Fig. 3 of the vided therefor in the forward portion of thecasing I is a tubular shaft III which projects forwardly through thehousing 8. An opening II isprovided in the housing 8 which accommodatesthe tubular shaft In. Journaled in the tubular shaft I0 is an innershaft I2 which extends forwardly and rearwardly from said tubular shaft.A bearing I3 is provided in the rear portion of the casing I for therear end portion ofthe inner shaft I2. It may be well to here state thatthe inner shaft I2 is adapted to be connected, at its rear end, to thecrank shaft of the engine 'I.

A beveled gear I4 is fixed on the tubular outer shaft IIJ between thebearings 9 and a similar gear I5 is fixed on the inner shaft I2rearwardly of the bearing I3. The gear I4 is connected to the gear I5for actuation thereby through a pinion gear I6 which is journaledhorizontally on a suitable hearing I! which is provided therefor in thelower section 3 of the casing I. Thus, the shafts I0 and I2 areoperatively connected together for rotation in opposite directions.

Fixed on the forward end portions of the shafts I (l and- I 2 are hubsI8. The hubs I8 include bushings 23 which are splined on the shafts IIIand I2, said bushings having flanges 24 on their ends. Mounted on thehubs I8 and projecting in opposite directions therefrom are singleblades I9. The hubs I8. are provided, in diametrically opposite sidesfrom the blades I9, with recesses 25 which accommodate substantiallysegmental counterweights 20, said counterweights being secured betweenthe flanges 24. These counterweights are shown to advantage in Figs. 5and '7 of the drawings. The reference numeral 2i desend portion of theshaft I2.

It is thought that the operation of the invention will be readilyapparent from a consideration ofthe foregoing. The shaft I2, which isdriven directly from the engine, rotates in one direction with its bladeI9 and the tubular shaft III, which is driven from the shaft I2 throughgears I5,

'ignates a nose which is mounted on the forward I6 and I4, rotates inthe opposite direction with its respective blade I9. Thus, the singleblades I9, being located in different vertical planes, travel in theirown paths and do not follow preceding blades, as isrthe case withpropellers of the multi blade type in widespread use at present. Thecounterweights 2a in the hub structures I8 reduce vibration to aminimum. Further, by reason of the fact that the blades I9 rotate in.opposite directions torque is reduced. The reference numeral 22designates an oil conduit connected to the casing I.

It is believed that the many advantages of a propeller constructed inaccordance with the present invention will be readily understood andalthough a. preferred embodiment of the device is as illustrated anddescribed. it is to be'underq stood that changes in the details ofconstruction and in the combination and arrangement of parts may beresorted to which will fall within the scope of the invention asclaimed.

What is claimed'is: A propeller of the character described com- '10prising a hub having a substantially segmentalrecess in its periphery, abushing extending centrally through the hub, integral flanges on theends of said bushing, a single blade projecting from the hub on thediametrically opposite side thereof from therecess, and a substantiallyseg- 'mental counterweight mounted in the recess on the bushing andsecured between the flanges,

the periphery of said counterweight beingflush with that Of the hub.

ELBERT HAWKINS.

